<!-- 图片上传组件 -->
<template>
  <el-upload
    v-model:file-list="fileList"
    list-type="picture-card"
    :class="fileList.length >= props.limit || !props.showUploadBtn ? 'hide' : 'show'"
    :before-upload="handleBeforeUpload"
    :action="props.action"
    :headers="props.headers"
    :data="props.data"
    :name="props.name"
    :on-success="handleSuccessFile"
    :on-error="handleError"
    :accept="props.accept"
    :limit="props.limit"
  >
    <i-ep-plus />
    <template #file="{ file }">
      <div style="width: 100%">
        <img class="el-upload-list__item-thumbnail" :src="file.url" alt="" />
        <span class="el-upload-list__item-actions">
          <span class="el-upload-list__item-preview" @click="previewImg(file)">
            <el-icon><zoom-in /></el-icon>
          </span>
          <span
            v-if="props.showDelBtn"
            class="el-upload-list__item-delete"
            @click="handleRemove(file)"
          >
            <el-icon><Delete /></el-icon>
          </span>
        </span>
      </div>
    </template>
  </el-upload>

  <el-image-viewer
    v-if="viewVisible"
    :zoom-rate="1.2"
    @close="closePreview"
    :initialIndex="initialIndex"
    :url-list="viewFileList"
  />
</template>
<script setup lang="ts">
import { UploadRawFile, UploadUserFile, UploadFile, UploadProps } from 'element-plus'
import FileAPI from '@/api/file'
import { TOKEN_KEY } from '@/enums/CacheEnum'
import { ResultEnum } from '@/enums/ResultEnum'

const emit = defineEmits(['update:modelValue'])

const props = defineProps({
  /**
   * 文件路径集合
   */
  modelValue: {
    type: Array<string>,
    default: () => []
  },
  /**
   * 上传地址
   */
  action: {
    type: String,
    default: FileAPI.uploadUrl
  },
  /**
   * 请求头
   */
  headers: {
    type: Object,
    default: () => {
      return {
        Authorization: localStorage.getItem(TOKEN_KEY)
      }
    }
  },
  /**
   * 请求携带的额外参数
   */
  data: {
    type: Object,
    default: () => {
      return {}
    }
  },
  /**
   * 上传文件的参数名
   */
  name: {
    type: String,
    default: 'file'
  },
  /**
   * 文件上传数量限制
   */
  limit: {
    type: Number,
    default: 10
  },
  /**
   * 是否显示删除按钮
   */
  showDelBtn: {
    type: Boolean,
    default: true
  },
  /**
   * 是否显示上传按钮
   */
  showUploadBtn: {
    type: Boolean,
    default: true
  },
  /**
   * 单张图片最大大小
   */
  uploadMaxSize: {
    type: Number,
    default: 2 * 1024 * 1024
  },
  /**
   * 上传文件类型
   */
  accept: {
    type: String,
    default: 'image/*'
  }
})

const viewVisible = ref(false)
const initialIndex = ref(0)

const fileList = ref([] as UploadUserFile[])
const valFileList = ref([] as string[])
const viewFileList = ref([] as string[])

watch(
  () => props.modelValue,
  (newVal: string[]) => {
    const filePaths = fileList.value.map((file) => file.url)
    // 监听modelValue文件集合值未变化时，跳过赋值
    if (
      filePaths.length > 0 &&
      filePaths.length === newVal.length &&
      filePaths.every((x) => newVal.some((y) => y === x)) &&
      newVal.every((y) => filePaths.some((x) => x === y))
    ) {
      return
    }

    if (newVal.length <= 0) {
      fileList.value = []
      viewFileList.value = []
      valFileList.value = []
      return
    }

    fileList.value = newVal.map((filePath) => {
      return { url: filePath } as UploadUserFile
    })
    valFileList.value = newVal.map((filePath) => {
      return filePath
    })
  },
  { immediate: true }
)

/**
 * 上传成功回调
 *
 * @param options
 */
const handleSuccessFile = (response: any, file: UploadFile) => {
  if (response.code === ResultEnum.SUCCESS) {
    ElMessage.success('上传成功')
    valFileList.value.push(response.data.url)
    emit('update:modelValue', valFileList.value)
    return
  } else {
    ElMessage.error(response.msg || '上传失败')
  }
}

const handleError = (error: any) => {
  ElMessage.error('上传失败')
}

/**
 * 删除图片
 */
function handleRemove(removeFile: UploadFile) {
  const filePath = removeFile.url
  if (filePath) {
    FileAPI.deleteByPath(filePath).then(() => {
      valFileList.value = valFileList.value.filter((x) => x !== filePath)
      // 删除成功回调
      emit('update:modelValue', valFileList.value)
    })
  }
}

/**
 * 限制用户上传文件的格式和大小
 */
function handleBeforeUpload(file: UploadRawFile) {
  if (file.size > props.uploadMaxSize) {
    ElMessage.warning('上传图片不能大于' + Math.trunc(props.uploadMaxSize / 1024 / 1024) + 'M')
    return false
  }
  return true
}

/**
 * 预览图片
 */
const previewImg: UploadProps['onPreview'] = (uploadFile: UploadFile) => {
  viewFileList.value = fileList.value.map((file) => file.url!)
  initialIndex.value = fileList.value.findIndex((file) => file.url === uploadFile.url)
  viewVisible.value = true
}

/**
 * 关闭预览
 */
const closePreview = () => {
  viewVisible.value = false
}
</script>
<style lang="scss" scoped>
.hide {
  :deep(.el-upload--picture-card) {
    display: none;
  }
}

.show {
  :deep(.el-upload--picture-card) {
    display: flex;
  }
}
</style>
